Compatibility issue with 2.4/2.5, Hyper-V, and Samsung SmartThings Hub
I realize this is a lot to type/read, thank you in advance. This issue took me about 3 weeks to figure out by elimination of factors until I found the one that is 100% repeatable..
My setup is a Hyper-V VM on Win10 (20H2). It is bound to a Quad Port Intel I350-T4. Three of its ports are exclusively set to their own vSwitch, and only pfSense uses those 3 vSwitches. hn0 is WAN, hn1.x is LAN/WORK, hn2 is lab.
I was having a repeatable problem every day, starting around 8:20am EST, and ending around 8:50am EST. During this time, network functionality in the LAN (hn1.50) & WORK (hn1.40) would cease. The WAN and LAB were unaffected.
pfSense System Logs showed "hn1 RXBUF ack retry" followed by many "hn1 RXBUF ack failed" messages in that time interval.
While troubleshooting this issue, I went from pfSense 2.4 to 2.5, hoping this would resolve itself. It didn't. I also started an entirely new pfSense VM from scratch. The problem continued to follow into the new VM.
I updated drivers for the I350-T4, firmware on the switch, windows OS patches, reinspecting hyper-v network configuration - everything on the host & switchign side looked good, but the problem continued.
I got to the point where I simply started unplugging network devices, one at a time, once a day, for a 24 hour period until something changed. That's when I discovered when I unplug the Samsung SmartThings hub, the problem stopped. I kept it offline for 3 days, problem went away. To test, I plugged it back in and left it overnight, and this morning the symptoms returned at the exact time window as before.
Has anyone else been having similar issues with Samsung SmartThings Hubs? This problem came out of nowhere, so I suspect a recent Hub firmware update may be the cause.